过E做EM⊥AB的延长线于M
则OBME是正方形
S△AME=1/2EM×AM=1/2×1/2AB×(AB+1/2AB)
=1/2×1/2×10×(10+5)=75/2=37.532.125
S弧BME=S正方形OBME-1/4半圆
=5²-1/4×5²×3.14
=25×(1-0.785)
=25×0.215
=5.375
∴S阴影=S△AME-S弧BME
=37.5-5.375
=32.125
过E做EM⊥AB的延长线于M
则OBME是正方形
S△AME=1/2EM×AM=1/2×1/2AB×(AB+1/2AB)
=1/2×1/2×10×(10+5)=75/2=37.532.125
S弧BME=S正方形OBME-1/4半圆
=5²-1/4×5²×3.14
=25×(1-0.785)
=25×0.215
=5.375
∴S阴影=S△AME-S弧BME
=37.5-5.375
=32.125